Chuck for taper pins and the like



Jam 1., 1924 M. c. KRlsTEK CHUCK FOR TAPER PINS ANDI THE L'IKE FiledMarch 5. 1921 yam?" 6 States), residing at Worcester, in the PatentedJan. l, '1924.

UNITED Sterns PATENT OFFICE.

CHUCK non Vfriirnn rms AND THE Linn Application filed March 5, 1921.Serial No. 450,017.

To all wlw/m t may concern.

Be it known that I, MARX C. KRISTEK, a citizen of Austria (who has takenout his first papers to become a citizenof the United county ofWorcester and State of Massachusets, have invented a new and usefulChuck for Taper Pins and the like, of which the following is aspecification. Y

This invention relates to a chuck capable of general use, but especiallyapplicable to a machine for operating on wire to produce a rapidsuccession'of articles therefrom and is particularly adapted for holdingtapered pins7 although with mechanical changes it can be arranged forother articles of a similar nature. Y

f The principal objects of the invention are to provide an improved formof chuck'for holding the wire or product in such a way as to firmly gripitwhether the work is straight'or tapered with no danger of the force ofthe gripping action being lostduring the operation; to provide anlimproved means for equalizing the action of the jaws; and to provide acl tch of novel construction which will obviate the common difficultywith screw machine clutches7 due to the fact that7 as formerlyconstructed, they had elements which would be caused to fly out bycentrifugal force and sometimes 'cause the chuck'to grip the wire so asto prevent feeding of the same.

- The invention also involves novel arrangements for operating the chuckand for ejectin the finished article.

urther objects and advantages of the.

invention will be hereinafter described and more particularly pointedout in ythel appended y claims.

Reference is to be had to the accompanying drawing in Vwhich-- Fig. lisa side view partly in central longitudinal section'showing a machinewhich involves the features of this invention; and F ig. 2 is asectional view of the clutch and -the chuck ina position for ejectingthe finished article from a taper pin machine.

The invention can be applied to a taper pin making machine of the screwmachine type provided with cams 18, 19 and 20 on a main cross shaft notshown but mounted on a frame 11. Although not shown herewith the machineis also provided with two Vother. cams `for operating al 'turning toolholder 23 and acutting ofia teni holder 24.

for grippingv the wire.

scribe the details at this `adapted to be 'reciprocated `in shaft 28 bythe cam 20. This 'which is fixed in The operation of these two ltoolholders is accomplished by swinging them on a shaft 25 on which they arepivotally mounted. As this is well understood in the screw machine art7I have not illustrated the details. This lrame 11 is provided Vwith anumber of bearings 26 in which are located two hollow shafts 27 and 28,one on the right or receiving end of the machine and t-he other 28 onthe left. The shaft on the right, as is truev with screw machinesgenerally, is provided with an internal hollow feeding in shaft 30rotating in an operating element 31 outside the shaft 27 and'centered inthat shaft. ThisV is provided with jaws, not shown, forA feeding thewire W inwardly according Vto Vthe reciprocating motion given to thehollow shaft 30 by a Icam 18. The

shaft 27 is not longitudinally movable but is yprovidedv with a drlvingpulley 32 for constantly rotating it. The same is true of the shaft 28.These two shafts tare rotated at the same speed. f

The shaft'27 also is provided with a clutch 33 operated by the cam 19 tomove back and forth and operate the chuck 34 in its end As I'have vshownduplicates of these two parts 33 and 34 on the other side of the machineI will not depoint.

Theshaft 28 as stated has an internal hollow rod 37 fixed in asupport29. The .end of this rodl 37 is filled by'a plug 38 which isprovided'with a stop 39 fixed, positively of course, to the rod 37.-Mounted to move on the rod 37 isa hollow shaft 40 which is the rotaryshaft 40 is provided with means by which it 1s reclp'rocated.

Slidable'on the shaft 28 is a sleeve 41 arranged to be reciprocated by acam. This is provided with an internal conical cam surface 42 and acylindricalV surface 43 at the end ofit for engaging and controlling setof jaw levers. These on studs 45 in a head 46 position on the rotatingshaft 28 by a screw threaded connection and pair of nuts 47 These jawlevers'44 are'L- shaped and it is to be noted that the arms whichoperate them are located inside the' surfaces 42 of the sleeve thatcontrol them. Therefore any increase in' centrifugal force, due to,excessive speed'for any cause, will not act to forte out these arms, orin fact.

levers are pivoted l face 5l. Tt will be is lcompleted and "the act uponthem at all. The inner ends of these arms project into slots 4S in thehollow shaft 40. Therefore, the motion of these levers on their pivotst5 will control the longitudinal motion of the shaft Li() in oppositionto a spring 22. This shaft 4:0 has screwed into its end and thereforesolidly fixed thereto, a hollowplug 50. This plug has an internalconical chuck operating surseen therefore that the operation of thesleeve if through the cam 2l controls the motion of this shaft 40 andtherefore the jaws 57.

A head 53 is mounted on the end of the rotary shaft 28. Tt is providedwith hollow spaces 54 and with an end plate 55 preferably bolted on, andopen at the center to permitthe entrance of the wire. The inside of thisplate 55 is provided with a conical surface 56 opposite the singleinside conical surface 51; Located in the three spaces 54, or in any'other desired'number arranged around the center, are a series of chuckjaws 57. These have conical or at least converging surfacesl forengagement with the two surfaces`51 and 56. A spring 58 is provided' foreach one, preferably a fiat spring entering a notch 59 in an extensionof the jaw, for holding these jaws outwardly as far as possible. Thisinsures their contact with the conical surfaces 5l and 56. A coil spring60 is shown as a convenient means for holding the jaws in properrelation tothe springs 58 without positively connecting these parts.independently 'of 4eachother and are free to swing a little either wayuntil tightenedv up. This provides for equalizing them so that theywill'be equally efficient in clamping a cylindrical object or -onetapering in either direction.v

The operation of the machine is as follows: The wire is forced clear into engage the end of the stop 39 which is stationary. The sleeve il4now` operates to move inwardlythe hollow shaft 40, against theopposition of its springs. This operation'takes place -through theaction of the cam surfaces 42 on'the'levers Lili as has been described.

Thus the head 50 is moved forwardly so as to positively move the chuckjaws`57 inwardly to 'grip the wire. The 'particular order of theoperation of the two cutting heads 23 and 2% is determined byv theirperating cams, the shapes of which are determined by the lind'ofw-orkbeing operated upon. But considering a single length of wire, thevEcutter 23 first operates on it and, as theV rotating wire moves along,the cutter swings inwardly toward the center so as to taper it. "Thisaction is produced by the operation ofthe cam which operates the cutteron holder" 23 as is'well understood. -Vihenjthe operation of forming ataper pin pin Acut olf itis held The jaws are hung.

Vstantly rotating hollow shaft, Vble head on said shaft, leversextending in the chuck. The opposite hollow shaft Q8 is now drawn backtaking with it the shaft 4.0 sliding on the stationary rod 37. Thisbrings the parts on the left back to the position shown in which thechuclr is drawn back so far that the stop 39 projects beyond its end.Therefore the tapered pin P, which had been in contact with the end ofthis stop, is necessarily ejected and drops out. Now the parts justdescribed move back again and the wire is moved in until the pin on itsend contacts with the end of the stop 39. Then the operations arerepeated.

Although T have illustrated and described only a single form of theinvention T am aware of the factthat modifications can be made thereinby any person skilled in the art without departing fromA the scope ofthe invention as expressed'in the claims.

Therefore, T do not wish to be limited to all of the details oflconstruction 'herein shown and described, but what T do claim is Y 1.ln a machine of the character described, the combination of'a constantlyrotating` external hollow shaft, an inner hollow shaft having` a fixedheadthereon provided with an internal slanting surface f at its end, aseries of independent jaws'hel'd in the end of the first named shaftkand ar ranged around it,"said first named shaft having surfacesengaging'the outer walls of said jaws, the inner linclined walls Aofsaid jaws engagingsaid surface, each jaw having a. notch, a flat springlsupported by the external shaft loosely engaging in e'ach notch to forceits jaw outwardly with a yielding action, and coil springs supported bythe external hollow shaft beyond the jawsr for engaging them at pointsopposite'the flat springs to hold the aws against the flatsprine's 2. lna machine of the character described, the combination of an externalcona reciprocathrough the shaft, a reciprocable inner hollow shafthaving notches for receiving :the

ends of said levers, whereby said inner shaft can beV movedlongitudinallyI by the head, said inner shaft having a: fixed headthereon provided with an internal conical surface atits end, a series oftriangular jaws individually held in the end 'of the `first named shaftVfree to move longitudinally therein and to swing, said first shafthaving inclinedv surfaces engaging the outer in.- clined walls ofv saidjaws, their inner inclined walls engaging said internal conical surface,whereby the iirst head will move the second vhead forwardly and forcethe jaws inwardly't-o effectively grip a wire or cone extending into thesecond'head, a notch in each aw,J a spring supported by the externalinternal slanting shaft extending into each notch to force its havinginclined surfaces engaging the outer 15 jaw outwardly with a yieldingaction, each inclined walls of said jaws, their inner injaw beingmounted independently of its clined walls engaging said internal conicalspring, and a second spring for holding the surface, each jaw having anotch, and a jaw in proper position with relation to the fiat springsupported by the external shaft first named spring. loosely engagingeach notch to force its jaw l0 3. In a machine of the characterdeoutwardly with a yielding action, said jaws scribed, the combinationof a constantly robeing mounted independently of the springs, tatinghollow shaft, an inner hollow shaft and yielding means for holding thejaws in having a fixed head thereon provided with proper position withrelation to the dat an internal conical surface at its end, a sprlng.25V

series of independent triangular jaws held In testimony whereof I havehereunto afin the end of the first named shaft and arfixed my signature.ranged around it, said first named shaft MARX C. KRIS'IEK.

